Loren Eiseley, the Poet of Evolution

Snippets from ‘The Firmament of Time’

In 1959, Loren Eiseley delivered a lecture called “How Death Became Natural” as part of a talk series held at the University of Cincinnati. In it Eiseley traced the historical progress of the concept of “species-extinction”, which had, until the 19th century, been fiercely resisted due to the widespread belief that in a world so benevolently governed by Providence, no created Forms would ever be allowed to disappear.

The talk begins with an eye-opening enumeration of some rather strange ideas about the history of life, most of which were put forward as scientists of the 17th, 18th, and 19th centuries dealt with (or dealt away with) growing fossil evidence that put strain on long-held theories; the talk ends with a poetic description of the view of life which eventually replaced those stubbornly persistent ideas— a description of evolutionary history which I find the most beautiful of any I’ve ever read on the topic.

I include entire passages here not only because of Eiseley’s unique and masterful prose style, but also because he brings up so many fascinating ideas that a summary simply wouldn’t do them justice. For the sake of readability, however, I present these excerpts with minor comments and modifications.

Without further ado, here’s Eiseley:

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Thomas Jefferson, writing in 1782, commented that “such is the economy of nature that no instance can be produced of her having permitted any one race of her animals to become extinct; of her having formed any link in her great work so weak as to be broken.”¹

The well-read Jefferson is, of course, merely repeating what was the commonly accepted view of his time. Extinction loomed as something vaguely threatening and heretical. In fact, for that very reason many refused to accept fossils as representing once-living creatures. Their reluctance to accept what now seems to us so easily discernible and commonplace an observation as extinction is based essentially upon one fact: the benignity of Providence.

“To suppose any species of Creatures to cease cannot consist with the Divine Providence,” writes one seventeenth-century naturalist, and his comment is frequently reiterated by others.² This point of view is based upon a theory of organic relationships which, though traceable into earlier centuries, reached a peculiar height of development during the seventeenth and eighteenth centuries. The belief was not confined to philosophy and theology. It permeated the whole field of letters and became widely known as the Scala Naturae, or Ladder of Being.

This conception superficially resembles a line of evolutionary ascent and undoubtedly has played an indirect part in the promotion of evolutionary notions of a scale of rising complexity in the development of life. It was not, however, a scheme of evolution. It is based on a gradation which emerged instantaneously at the moment of creation, and which rises by imperceptible transitions from the inorganic through the organic world to man, and even beyond him to divine spiritual natures.

The idea promoted much anatomical work of a devout character as naturalists attempted to work out the missing or obscure links in what was regarded as an indissoluble chain which held together the various parts of creation. It was for this reason that men viewed with genuine horror the idea that links could be lost out of the chain of life. The strong belief in an all-wise Providence which did nothing without intention caused men to refuse an interpretation of the universe which involved apparently aimless disappearances. If such disappearances were possible, what might not happen to man himself?“

Eiseley then goes through the different epicycles used by the scientific establishment to “save the appearance” of a divinely-balanced world. Most of them involved questionable interpretations of a burgeoning fossil record which routinely yielded shapes nobody had ever seen roaming about in their farm or forest.

One of these so-called epicycles— motivated by the outright denial of species-extinction—was the historicizing of fossils. For example, when mammoth skeletons were found in Europe they were instead taken to be the remains of Hannibal’s elephants, or of animals collected for ancient Roman games.

In the case of fossils we must remember how small the European domain of science was in comparison with the vast continental areas which had only recently been opened for examination by the voyagers. Australia, Africa, the Americas, were barely known; their interiors remained unexplored. They provided a providential escape for the devout naturalist who still wished to avoid the dangerous logic implicit in unknown bones and shells.

Since it was beginning to be realized that the separate continents possessed faunas and floras to some degree distinct, the devout could argue that creatures of which there were now no living representatives in Europe might well have been driven out by man, or by changes of climate; in short, that instead of being extinct, they had merely retired to the fastnesses of unknown seas or continents. Jefferson quotes an observer who had heard the mammoth roaring in the Virginia woods. In Europe the bones of Ice Age elephants were ascribed to the living African species imported, so it was claimed, for Roman games. Or the bones were those of Hannibal’s war elephants lost on the Alpine passes. The desired point was to make the animals historic and thus ascribable still to living species [emphasis mine]. In America, where great bones lay in profusion, it was rumored that living specimens could be found across the unknown Great Lakes or farther on in the heart of the continent.

But as fossil evidence increased of creatures ever more clearly unrelated to those still extant, some way of harmonizing the new evidence with the Biblical picture proved necessary. So a yet more absurd notion arose, aptly called “catastrophism”, which held that periodic cataclysms wiped the earth clean for a new, superior batch of life to emerge in the aftermath—the creation of the new animals modeled according to Forms stored safely within the mind of God. Each cleaning and repopulation of the planetary slate was believed to have paved the way for Nature’s pre-eminent children: Homo sapiens.

“At certain periods in the development of human knowledge,” C. D. Broad once remarked, “it may be profitable and even essential for generations of scientists to act on a theory which is philosophically quite ridiculous.”³ This was true in a comparatively short-lived way of catastrophism. It persuaded man to accept both death and progressive change in the universe. It did so by extending such mythological events as the world-shattering Biblical Deluge, and by the creation of a form of geological prophecy which left man still the dominant figure in his universe.

“Half a century ago,” wrote the great American botanist Asa Gray, who died in 1880, “the commonly received doctrine was that the earth had been completely depopulated and repopulated over and over; and that the species which now, along with man, occupy the present surface of the earth, belong to an ultimate and independent creation, having an ideal but no genealogical connection with those that preceded. This view . . . has very recently disappeared from science.”⁴

This was the philosophy which Sir Charles Lyell was destined to overthrow; this was the view propounded to young Charles Darwin by his geology professors before he went on the voyage of the Beagle. [bolds mine]

…But in what lay the vitality of this weirdly irrational theory, and how did it arise?

…There arose among German and French nature philosophers a renewed sense of the unity of plan or biological structure common to large groups of plants and animals—a morphological advance also marked by the contributions of Cuvier in France and his disciple, Richard Owen, in England. The transcendental aspects of this morphology lay in the conception that these major structural plans existed abstractly in the mind of God, who altered them significantly from age to age. In the words of Adam Sedgwick⁵, Darwin’s old teacher, “At succeeding epochs, new tribes of beings were called into existence, not merely as the progeny of those that had appeared before them, but as new and living proofs of creative interference; and though formed on the same plan, and bearing the same marks of wise contrivance, oftentimes as unlike those creatures which preceded them, as if they had been matured in a different portion of the universe and cast upon the earth by the collision of another planet.”

It was generally conceived that the lower and earlier forms of life pointed on directly to man, who had been ordained to appear since the time of the first creation. “It can be shown,” asserted Louis Agassiz, “that in the great plan of creation . . . the very commencement exhibits a certain tendency toward the end . . . The constantly increasing similarity to man of the creatures successively called into existence, makes the final purpose obvious . . .”⁶

The geological record was being searched for signs and portents pointing to human emergence at a later epoch. There is more than a hint of medieval “signs in the heavens” to be found in these paleontological auguries: a reptile leaving hand-like imprints on some ancient sea beach is a portent of man’s coming; the stride of a bipedal dinosaur discloses the eventual appearance of bipedal man. [bolds mine]

Catastrophism, if we are to examine it in its most mature form—that of England in the second decade of the nineteenth century—has, as we have seen, several surprising features. The deathless Eden of the Biblical first creation has been replaced by a succession of natural but successive worlds divided from each other by floods or other violent cataclysms which absolutely exterminate the life of a particular age. Divinity then replaces the lost fauna with new forms in succeeding eras. Disconformities in geological strata, breaks in the paleontological record, are taken as signs of world-wide disaster terminating periods of calm.

In contrast to eighteenth-century concern over the death of species, and anxiety to establish seemingly extinct animals as still in existence, the natural theologians now revel in violence as excessive as that of the Old Testament. Whole orders of life are swept out of existence in the great march toward man. The stage which awaits the coming of the last great drama has to be prepared. Floods destroy the earlier actors. Enormous death demands equally enormous creation, discreetly veiled in the volcanic mists that hover over this half-supernatural landscape.

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Eiseley finally concludes his lecture with this, among my all-time favorite passages of prose:

All the way back into Cambrian time we know that sunlight fell, as it falls now, upon this planet. As Lyell taught, we can tell this by the eyes of fossil sea creatures such as the trilobites. We know that rain fell, as it falls now, upon wet beaches that had never known the step of man. We can read the scampering imprints of the raindrops upon the wet mud that has long since turned to stone. We can view the ripple marks in the sands of vanished coves.

In all that time the ways of the inanimate world have not altered; storms and wind, sun and frost, have worked slowly upon the landscape. Mountains have risen and worn down, coast lines have altered. All that world has been the product of blind force and counterforce, the grinding of ice over stone, the pounding of pebbles in the mountain torrents—a workshop of a thousand hammers and shooting sparks in which no conscious hand was ever visible, today or yesterday.

Yet into this world of the machine—this mechanical disturbance surrounded by desert silences—a ghost has come, a ghost whose step must have been as light and imperceptible as the first scurry of a mouse in Cheops’ tomb. Musing over the Archean strata, one can hear and see it in the sub-cellars of the mind itself, a little green in a fulminating spring, some strange objects floundering and helpless in the ooze on the tide line, something beating, beating, like a heart until a mounting thunder goes up through the towering strata, until no drum that ever was can produce its rhythm, until no mind can contain it, until it rises, wet and seaweed-crowned, an apparition from marsh and tide pool, gross with matter, gurgling and inarticulate, ape and man-ape, grisly and fang-scarred, until the thunder is in oneself and is passing—to the ages beyond—to a world unknown, yet forever being born.

“It is carbon,” says one, as the music fades within his ear. “It is done with the amino acids,” contributes another. “It rots and ebbs into the ground,” growls a realist. “It began in the mud,” criticizes a dreamer. “It endures pain,” cries a sufferer. “It is evil,” sighs a man of many disillusionments.

Since the first human eye saw a leaf in Devonian sandstone and a puzzled finger reached to touch it, sadness has lain over the heart of man. By this tenuous thread of living protoplasm, stretching backward into time, we are linked forever to lost beaches whose sands have long since hardened into stone. The stars that caught our blind amphibian stare have shifted far or vanished in their courses, but still that naked, glistening thread winds onward. No one knows the secret of its beginning or its end. Its forms are phantoms. The thread alone is real; the thread is life.

“Nevertheless, there is a goal,” we seek to console ourselves. “The thread is there, the thread runs to a goal.” But the thread has run a tangled maze. There are strange turns in its history, loops and knots and constrictions. Today the dead beasts decorate the halls of our museums, and that nature of which men spoke so trustingly is known to have created a multitude of forms before the present, played with them, building armor and strange reptilian pleasures, only to let them pass like discarded toys on a playroom floor. Nevertheless, the thread of life ran onward, so that if you look closely you can see the singing reptile in the bird, or some ancient amphibian fondness for the ooze where the child wades in the mud.

One thing alone life does not appear to do; it never brings back the past. Unlike lifeless matter, it is historical. It seems to have had a single point of origin and to be traveling in a totally unique fashion in the time dimension. That life was ever a fixed chain without movement was a human illusion; that it leaped as some mystical abstraction from one giant scene of death to another was also an illusion; that geological prophecy proclaimed the coming of man as Elizabethan astrologers read in the heavens the signs of coming events for kings was an even greater fantasy. Instead, species died irregularly like individual men over the long and scattered waste of eons. And as they died they must, as Lyell foresaw, be replaced in as scattered a fashion as their deaths. But what was the secret? Did a voice speak once in a hundred years in some hidden wood so that a nocturnal flower bloomed, or something new and furry ran away into the dark?

Creation and its mystery could no longer be safely relegated to the past behind us. It might now reveal itself to man at any moment in a farmer’s pasture, or a willow thicket. By the comprehension of death man was beginning to glimpse another secret. The common day had turned marvelous. Creation—whether seen or unseen—must be even now about us everywhere in the prosaic world of the present.

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Eiseley’s next lecture, following the theme of the series, discusses “How Life became Natural”, how after the fact of species-extinction became undeniable, the question of how new forms emerge became impossible to ignore. Those with some idea of the history of biology can guess what happened next.

After all the theoretical false-starts and speculation in understanding the history of life, which Eiseley likens to the variegated noise of an uncoordinated orchestra, it would take a Darwin to finally seize the conductor’s baton and turn all those spurts of sound into music. If species all around us, all the time are going extinct and disappearing forever, so too, Darwin said, “endless forms most beautiful and most wonderful have been, and are being evolved.”

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For more of the story (which you may not know as well as you think), I’m afraid you’ll have to pick up The Firmament of Time! And if you’re less specifically interested in the history of evolutionary theory, Eiseley’s essay collection The Immense Journey is also stupendous. I’m not even kidding when I say passages like those above, which balance heart-stopping prose with an air of humorous and humane Reason, are pretty common with Eiseley. He may be the most underrated and overlooked writer I know of.

1. Notes on the State of Virginia (1785), chapter 6

2. William Cole’s letter of March 27, 1685, to John Ray, collected in Philosophical Letters between the Late Learned Mr. Ray and Several of His Ingenious Correspondents, Natives and Foreigners (1718)

3. Broad’s “The New Philosophy: Bruno to Descartes,” Cambridge Historical Journal, January 1944.

4. Natural Science and Religion: Two Lectures Delivered to the Theological School of Yale College (1880), lecture 1 (“Scientific Beliefs”).

5. A Discourse in the Studies of the University (1833)

6. “A Period in the History of Our Planet,” Edinburgh New Philosophical Journal, July–October 1843.